weekly reports spring 2015 weekly report of 28 march, 2015 · 2018-09-10 · weekly reports spring...

WEEKLY REPORTS

SPRING 2015

Weekly Report of 28 March, 2015

Spring has officially started, but migration is lagging behind. Many of the species we expected to see have not arrived yet. The only ones we found were Willow Warbler and Tree Pipit – only one of each, though. In any event, species variety remained very high, and we even had a couple of local rarities: a Subalpine Warbler (the 5th record in 15 years) and a Golden Plover. Green Sandpipers have reached peak numbers, with several dozen present, and Black-winged Stilts increased to 55; among the waterfowl, twenty or so Shovelers stood out, while Garganeys were quite scarce. The only songbird present in good numbers was the Blackcap. The checklist was rounded out by Goshawk, Spotted Crake, Coal Tit, Serin, Great Bittern, Hen Harrier and all the other regulars, for a total of 79 species. For the first time this year, good numbers of butterflies were out and about: we saw eight species, including a Large Tortoiseshell (Nymphalis polychloros), a local rarity. Among the other insects that are back on the wing, bumblebees and hornets were particularly conspicuous. Only the large queens – the only members of their species to have survived the winter - are active. As large as she is, a hornet queen is truly a fearsome sight.

WEEKLY REPORTS

SPRING 2015

Weekly Report of 04 April, 2015

Stormy weather arriving during a night of full moon: the conditions seemed

perfect for a fall of songbird migrants. Our great expectations were followed by a big letdown.

The hedgerows, bushes, and trees were still and silent, lifeless. Passerine migrants seemed completely absent. After all, it’s part of the lure of

birdwatching: you never know who is going to take the stage. In fact, sometimes the show is cancelled altogether.

Luckily, waterbirds put on a good performance today, especially waders: over 100 Ruff, 70 Black-winged Stilts, 50 Green Sandpipers, a dozen each of Wood

Sandpiper, Little Ringed Plover, and Greenshank, 7 Spotted Redshanks, a few Snipe and Lapwings, and best of all, a Ringed Plover, only the third record ever

at La Cassinazza. It was wonderful to watch them all together on the same

mudflat, and they put on a pretty good concert as well, since the Green Sandpipers, Black-winged Stilts, Greenshanks, and plovers were all calling

continuously. The fifty Garganeys were a feast for the eyes, if not for the ears.

New arrivals this week included

Purple Heron, Wryneck, and a Sedge Warbler timidly singing

from deep within the reedbed. The very first Mallard chicks have

already hatched.

We frequently ran into a Great Bittern or two during mid-winter,

but they disappeared in February

and much of March. We saw one again today: perhaps this means

that the wintering individuals are gone and have been replaced by

new birds here for the spring.

WEEKLY REPORTS

SPRING 2015


Waders stole the scene once again today. Not that there weren’t any other birds: a few singing Nightingales, a Common Whitethroat, a Hoopoe, and the first Common Terns on the lake were all seasonal firsts; a few Willow Warblers and Chiffchaffs, and a small flock of Siskins were also around. But these were only a few scattered individuals of those species, if not a single bird – just enough to check them off on our list. Many of the spring migrants that should already be here are nowhere to be found. Only the Blackcaps were abundant, and such was the variety of their songs that they often tricked our ears and sent us off to chase inexistent, unknown birds. Waders stood out for their variety - 12 species, including a locally-uncommon Marsh Sandpiper – and for some, their numbers as well, with about 90 Black-winged Stilts, 30 Greenshanks, and 50 Wood Sandpipers. Over time, reptiles have colonized La Cassinazza: it is increasingly common to run into Western Whip Snakes and Grass Snakes, especially on the first sunny days of spring. The former feeds on lizards and small rodents, the latter on frogs. The Grass Snake in the photo, which was crossing a dirt path, could neither run away nor hide: huffing and puffing, it coiled onto itself, trying to do its best viper impersonation.

WEEKLY REPORTS

SPRING 2015


It’s amazing how much the vegetation grew in just one week. Now all the trees and bushes are in full leaf and conceal small birds, which remain scarce to boot. Nevertheless, numerous species put in their first appearance of the year: Cuckoo, Little Bittern, Turtle Dove, Wood Warbler, and Pied Flycatcher. Waders once again were the highlight, with Wood Sandpipers and Black-winged Stilts both in the triple digits, in addition to smaller numbers of Lapwings, Little Ringed Plovers, Green Sandpipers, Common Sandpipers, Common Snipe, and a single Black-tailed Godwit. Black-winged Stilts are busy building their nests, and at least ten pairs have already laid eggs. Raptors were also much in evidence, highlighted by a Pallid Harrier and a Lesser Kestrels, both rare migrants at La Cassinazza. The list is rounded out by two migrating Hobbies, a Peregrine, two Black Kites, and the usual Buzzards and Sparrowhawks. The Marsh Harrier pair can often be seen displaying above the reedbed. The only noteworthy ducks were 20 Garganey, while not a single Teal remains. Finally, we saw Great Bittern, Yellow Wagtail, and Tree Pipit, and heard singing Hoopoe and Wryneck. A Black Stork overhead was undoubtedly a migrant. Early in the morning, the chilly temperature and the moisture in the air made for dense fog, which immediately lifted as soon as the sun appeared and set the tender poplar leaves aflame.

WEEKLY REPORTS

SPRING 2015


After several weekends of sunny skies and active migration, today all was calm and placid. The weather looked uncertain – we could never tell whether it was about to rain, or if the sun was getting ready to peek out from behind the clouds. All day long it felt as if we were on the verge of a burst of activity, yet the birds remained quiet, and the cold and cloudy weather meant few if any insects were about. In spite of this, we managed to find 64 species over the course of the day, thanks to the varied habitats that brought us both songbirds in the hedgerows and waterbirds in the wetlands. The Marsh Harriers are continuing their courtship flights, and it won’t be long before the female will disappear into the reedbed to incubate her eggs. The female Red-footed Falcon that passed quickly overhead is still far from starting a family – she was headed for other parts of Europe. Wader diversity was essentially the same as last week – mostly Wood Sandpipers, Greenshanks, Ruff, Spotted Redshanks, and Little Ringed Plovers – but their numbers dropped somewhat. The Black-winged Stilt colony is in full swing. The highlight of the day consisted of three Temminck’s Stints, cute, tiny waders using La Cassinazza’s impoundments as a stopover on their migration from Africa to the Siberian tundra. The Great Crested Grebe pair is still on the lake, where we hope they will be able to nest successfully, in spite of the danger to chicks caused by the presence of the voracious Wels Catfish.

WEEKLY REPORTS

SPRING 2015

Weekly Report of 02 May, 2015

After the rain overnight, the unsettled weather moved on. In the clear dawn, the landscape was steamy with fog and dripping water. Spring migration is ending: lingering migrants included about 50 Wood Sandpipers, a smaller number of Ruff, several Pied Flycatchers, and two or three Honey Buzzards. The tail end of migration did bring us an exceptional surprise: a Grasshopper Warbler singing from a hedgerow. It is a little brown job, practically invisible to boot, and can only thrill the most hardcore birding fanatics like us. Now is the time to turn our attention to breeding birds. There are at least 12 active Black-winged Stilt nests; since about 90 individuals are around, we expect quite a few more nests in the coming weeks. Two or three Common Tern pairs are already on eggs, but since the colony comprises 9-10 pairs, more will be incubating soon. The White Storks let us down: the pair at Cascina Darsena remained faithful to its regular nest for the fifth year in a row, but the two pairs that nested at La Cassinazza last year only put in brief visits before leaving. One has built a new nest on the church tower in the hamlet of Baselica, which is only 500 meters away, but outside of the Cassinazza property. The rainfall certainly affected the local insects, and butterflies and dragonflies were quite scarce today. The appropriately-named Orange Tip (Anthocharis cardamines) only flies for a few weeks in spring, and is rather uncommon at La Cassinazza.

WEEKLY REPORTS

SPRING 2015


Unseasonal heat and humidity made for a summery, slightly stifling day. Bird

activity, which was slow to begin with, quickly stopped altogether. We only had two or three hours of productive birdwatching.

These brought us a Whinchat and a magnificent male Red-backed Shrike, both firsts for the year.

In spite of its great height, we can see the chicks in the White Stork nest at Cascina Darsena, as their mother perches on the brim of the nest to take care

of them. Meanwhile, the pair on the church belltower is still incubating. Poplar seeds have matured. Last night’s thunderstorm knocked them down,

but as early as the afternoon the trees were once again producing vast quantity of wooly down, which works its way into everything, irritating throats

and nostrils.

Butterfly numbers are still low, although we saw the year’s first Large Coppers (Lycaena dispar) – a male and three females.

Over the last few weeks, the Marsh Harrier pair has become very cautious: they are no longer performing display flights or other territorial behaviours,

and have become nearly invisible. This is a clear sign that they have laid eggs, and are now engaged in the delicate incubation phase. We needed quite a bit

of patience, and a stroke of good luck, to glimpse the female as she flew back to her nest after a brief foray. The nest itself is out of sight in the densest

patch of reeds.

The male hunts for two, flying low against

the vegetation and never high in the sky.

Its unmistakable

silvery wings with black tips make it

stand out.

WEEKLY REPORTS

SPRING 2015


We can safely say that spring migration is behind us, and ornithological summer is upon us. The last lingering Garganeys have left; the waterfowl contingent is now made up exclusively of Mallards, about 200 or so, mostly drakes. The hens are busy attending to their brood and scattered throughout the countryside. The only waders left are Lapwings and Black-winged Stilts, both of which are breeding. The stilt eggs have hatched: most of the nests are now screened by tall grass, but the adults’ aggressive behaviour speaks volumes. It was only later that we managed to see a few chicks, ranging from one day to about a week old. We won’t have to wait long for wader variety to pick up again: in less than a month, the first fall migrants will be on their way south. The latest of the breeding passerines, the Marsh Warbler, has arrived, and is in full song. Butterfly variety is beginning to increase, with 15 species recorded today. The most noteworthy was the Small Tortoiseshell (Aglais urticae), which is quite uncommon in the plain. Dragonflies are still scarce, with the exception of the White-legged Damselfly (Platycnemis pennipes): one just needs to approach the plants where newly-emerged individuals are resting to flush scores of them.

Once again we found Red-backed Shrike, two individuals this time. This is one of the many – too many - species that have undergone a dramatic population decline in recent years: they were once routine breeders at La Cassinazza. We hope at least one pair will settle in this summer.

WEEKLY REPORTS

SPRING 2015


Dawn is the time for bird song. Now that Nightingales and Blackcaps are beginning to quiet down, the newly-arrived Marsh Warblers dominate the morning chorus. In optimal habitat – reed-lined ditches – we could hear one singing about every 50 meters. The poor weather, with cloudy skies and cold temperatures, forced a great many Barn Swallows, Common Swifts, and House Martins to hunt for insects low over La Cassinazza’s impoundments, with Sand Martin among them. For a while it looked like this would be our sole birding highlight, as the day appeared rather uneventful otherwise. However, our persistence paid off with close looks at an Osprey, a young bird perched low on some branches hanging over the water. We had never seen one at this time of year, but non-breeding immatures are in no hurry to get to their summer range, and can spend quite some time just wandering around. Honey Buzzards also like to take it slow, and their migration continues until the end of May. Although we saw several today, the attached photo is from last Saturday. Also late are the honeysuckle and privet, which are flowering only now, among the latest bushes to do so. Their scents overlap – although that of honeysuckle is stronger and dominant – and the breeze carries them everywhere.

WEEKLY REPORTS

SPRING 2015


The Spotted Flycatcher was the last of the summer species still missing; they arrive well into May, and we had not seen one until today. It was the 150th species of the year. This is not only a nice round number, but also an exceptional total, showing that 2015 has been a truly extraordinary year in terms of the variety of birds we have seen at La Cassinazza. Ordinarily, we hope to break the 150 species barrier during the last month of the year, perhaps helped by a cold snap that might have pushed an uncommon winter visitor or two our way. This year, we managed to do this in just five months. In addition to numerous locally-rare species, spring 2015 gave us several birds that are quite scarce on a national scale as well. Another cause for celebration is the birth of the White Stork chicks in the nest on the bell tower at Baselica. As if that weren’t enough, we also found a new butterfly for La Cassinazza: an elusive, hard-to-find species listed under four different scientific names in the four books I consulted. While waiting for the entomologists to make up their mind, I will refer to it by its English name of Purple Hairstreak, which actually describes it rather well. It is exclusively tied to oaks; the caterpillars eat their leaves and the adults fly around their canopy, without descending to ground level. They are not attracted to flowers and feed exclusively on the sugary secretions produced by aphids. I was quite lucky to find one at eye level. It gave me just enough time for a couple of quick snaps before flying up and disappearing.

WEEKLY REPORTS

SPRING 2015

Weekly Report of 06 June, 2015

The early heat wave of the last few days put an end to any hopes of productive

birdwatching. Even in the early morning hours, only a few birds were singing, and even fewer were out and about. We had only two sightings worth relating.

The first was an Osprey briefly flying over. I assume it is the same individual we saw two weeks ago. It may be spending the summer in the Ticino

floodplain, and making a detour to La Cassinazza every now and again. Later on we saw the Spoonbill pair with at least three juveniles in tow.

Breeding was successful this year, it seems. The same can be said of the Black-winged Stilts. Apparently, almost every

clutch laid (about 20 active nests) hatched successfully. Many chicks and juveniles can be seen, ranging in ages from one day to one month, and we

observed no replacement clutches.

On the whole, insects also seemed to eschew the sticky heat. Of note were the year’s first Common Clubtail (Gomphus vulgatissimus), a dragonfly that

recently colonized La Cassinazza, and a Queen-of-Spain Fritillary (Issoria lathonia), a butterfly that only appears here occasionally. Both proved wary

and elusive.

The Squacco Heron, hunkered down in the thick vegetation, also looks as if it is trying to escape the sun’s rays.

WEEKLY REPORTS

SPRING 2015


We’re not even halfway through June, and the first fall migrant is already here:

a Green Sandpiper. The last spring migrants of this species came through at the end of April. In the coming weeks, until the end of July, we will see them

once again, this time headed in the opposite direction. The White Stork chicks at the Cascina Darsena nest are now big enough to

stand up, and this made it possible for us to count them. Once again, there are four of them. The Cascina Darsena pair, which used that nest for the first time

in 2011, fledged four juveniles each year except for 2012, when the entire brood was lost, perhaps due to a violent thunderstorm. So far, they have thus

raised a progeny of sixteen. Soon enough, we will know how the pair at Baselica fared.

Brief showers alternated with sunshine today. Insects were the main source of interest, and highlights included two new odonates for the year, Common

Spreadwing (Lestes sponsa) and Broad Scarlet (Crocothemis erythraea). I won’t bore you by listing all the beetles I found, but noteworthy records

included the large, emerald-green Protaetia aeruginosa, the largest species in the subfamily Cetoniinae. Turning to butterflies, we were glad to find several

Large Chequered Skippers (Heteropterus morpheus), a wetland species that had all but disappeared from La Cassinazza. I was even happier to be able to

take a close-up photo of it.

WEEKLY REPORTS

SPRING 2015


As I said last Saturday, the first thing I did today was to check the White Stork

nest at Baselica: only one juvenile is present. This is not exactly a successful pair, given that last year they did not even manage to hatch any eggs. Most

likely, these are young and inexperienced birds. White Storks are long-lived, and they will have plenty of time to learn how to do things properly.

As soon as a Marsh Harrier or Black Kite encroaches on one of their territories, the four local Hobbies set off in patrol flight, and if needed they chase the

intruder away. This means they are breeding: Hobbies are late breeders and are the last of the local species to lay eggs.

All the other birds have finished breeding, although a few species are busy

with a second brood: tits, Starlings, and Blackbirds. Blackbirds can breed

several times a year – they never stop. The males thus have reason to sing through the summer. At this time of year, the Blackbirds’ loud songs begin to

ring out well before five in the morning. We could do without it.

It was a crisp, sunny day, the best conditions for

watching insects. A great variety of butterflies – 21

species – were about. The most interesting

were the Silver-washed Fritillary (Argynnis

paphia), which we added to La Cassinazza’s

checklist only last year,

and especially the White-letter Hairstreak

(Satyrium w-album), which we had not seen in

three years. The larvae and adults of this species

both live in the canopy of elm trees and are rather

elusive. They are usually only seen when they

come down to feed on bramble blossoms.

weekly reports spring 2015 weekly report of 28 march, 2015 · 2018-09-10 · weekly reports spring...

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